The present invention relates to a circuit for testing the performance of a channel terminal and, more particularly, to a remote test circuit for controlling only one of multiple channel terminals whose address is designated into a return test mode to make it active.
Heretofore, a remote test on a channel terminal of the type described has been performed by setting up a return path. A remote test circuit built in a channel terminal consists of a return set signal detecting circuit and a return setting switch. In response to a detection output of the detecting circuit, the switch is controlled to form a return path.
A problem with the prior art remote test circuit as stated above is that in the case of multi-point connections as typified by 1:N (=4) communication it is impossible for a particular channel terminal to be designated for a test.